Many challenges remain opening regarding the integration of diamond into electronic devices. In particular, seeding processes are typically harsh on the substrate surface, leading to defect creation and lack of reproducibility. Iron-based materials have been used as catalysts in the synthesis of crystalline diamond by high temperature, high-pressure growth. Yet, it is difficult to fabricate diamond on iron-based materials by chemical vapor deposition (CVD) due to the rapid diffusion of carbon into the bulk and high carbon solubility. There have been a number of attempts to grow diamond by forming a thin film of iron on silicon substrates. Higher diamond nucleation densities with significant amounts of a-C are attained by depositing a thin layer of iron on silicon substrates, thus suggesting that a high carbon concentration resulting in a saturated carbide layer during the initial stage of nucleation is required for producing diamond nucleation sites. The prior art further indicates that there is an optimum iron thickness at which diamond growth prevails.
Thus, there exists a need for an efficient process that selectively yields high quality diamond films at relatively high growth rate with negligible co-deposition of amorphous carbon, and avoids any pre and post treatment of the substrate in order to prevent any undue damage to it.